###LIST_ID_IN_PROGRESS and LIST_ID_IN_DONE
List IDs seem to be a (board id + list index), where all are treated as hex numbers. However, this is undocumented.

Safe way to find a list ID is to open a card from the list, click the More link in the bottom-right corner, select Export JSON and find the idList.

Post receive will move all referenced cards to the LIST_ID_IN_PROGRESS, unless they are referenced by Close or Fix word, in which case it will move them to the LIST_ID_IN_DONE.

###commit_url_prefix
If you have a web view of your Git repo (such as GitLab), you can enter the URL which, when sufixed with the commit SHA will show the commit in question. Post-receive will add a link to the commit to each of the comments on cards.